This invention relates generally to signature folders, stackers, and bundlers used in the printing industry that produce heavy bundles of signatures ready to be bound together to form books. More particularly, the present invention relates to a signature bundle inverter that inverts a heavy bundle of signatures from a stacking machine prior to delivery of the bundle to a binding machine so that the signatures are in a proper orientation for use in the binding machine.
In the publication industry books are manufactured using signatures which are a collection of four, eight, sixteen, or thirty two pages folded together and bound into books. With some existing stacking machines, signatures are formed and deposited on a receiving rack in a position that is inverted from a position that can be used in a binding machine. Consequently, a bundle of signatures must be inverted prior to being transported to a binding machine. Typically, the inversion process is done by "pocket feeders" in a bindery which must flip a bundle of signatures a lift at a time. Worker injuries, downtime, and high insurance costs all result from repetitive manual inversion of signature bundles. Numerous machines are used to handle bundles of signatures (see for example: Steinhart, U.S. Pat. No. 4,183,704; Kasamatsu et al., U.S. Pat. No. 4,725,180; Palamides, U.S. Pat. No. 5,353,576; and Kleinhen, U.S. Pat. No. 5,392,700). None of the prior signature handling machines receives vertical bundles of signatures directly from a stacking machine and inverts them to a position usable in a binding machine.
Thus, there is needed a signature bundle inverter that minimizes the use of manually lifting signature bundles and inverts the bundles quickly and efficiently for proper orientation prior to delivery to a binding machine.